Portable bench sander



y 1934. H. L. MYERS PORTABLE BENCH SANDER Filed Sept. 5, 1931 5 Sheets-Sheet 1 Inventor fla/rry Z Myers flllomey July 31, 1934. MYERS 1,968,257

- PORTABLE BENCH SANDER I I Filed Sept. 5, 1931 s Sheets-Sheet 2 Jays? Inventor 19%)? .Z. Meks July 31, 1934. MYERS PORTABLE BENCH SANDER Filed Sept. 5, 1931 5 Shee ts-Sheet 3 July 31,1934. H YERS 1,968,257

PORTABLE BENCH SANDER Filed Sept. 5, 1931- 5 Sheets-Sheet 4 Inventor He/rryi. Ali era July 31, 1934.

H. 1.. YERS 1,968,257

PORTABLE BENCH SANDER Filed Sept. 5, 1931' 5 Sheets-Sheet 5 Patented July 31, I934 'UNITED STATES; PATENT OFFl-CE- PORTABLE BENCH SANDER Barry L. Myers, Toledo, Ohio, asslgnor to The American Floor Surfacing Machine Company, Toledo, Qhio Application September 5, 1931, Serial No. 561,478

Claims. (Cl. 51-170) This invention relates to an improved portable Fig. 9 is an enlarged detail section of the admachine 'for abrading and sanding work emjustable idler pulley. ployed in working, dressing, and finishing wood Fig. 10 is a horizontal sectional and elevational surfaces, the general characteristics of said maview illustrating the mechanical relationship of 5 chine being such as to permit'it to be conventhe idler pulley, to the frame and the spring- 63 iently entitled Portable bench sander. pressed tensioning and thrust device.

In developing the improved machine, I have Fig. 11 is a fragmentary sectional and elevaendeavored to provide a worthy contribution to tional view on a horizontal plane through a porthe trade and art-which may be used to advantion of said thrust connection.

tage in innumerable manners. Fig. 12 is an elevational view of a special 85 The purpose of the invention is to provide a pendulous-like fixture. light-weight belt sander with exceptional speed, Fig. 13 is top plan view of the fixture repreabundant electric power, and assured dependasent d in 12, bility for a i g and completely ondi i ni Fig. l'is a perspective view of a retaining leaf 315' work of all characters in cabinet shops, furniture spring 70 manufacturing establishments, wood-working one of the major parts of the improved inamills, and n fact by any One dealing with fiat chine is generally distinguished and denoted by Wood Surfaces equir g Surfacing preparatory the numeral 15, and this may be referred to altertO finishing a paintingnatively as the frame or chassis. This fe comat te pret d otherwise, I have evolved and prises, as seen in Fig.2, a substantially horizontal W duced a satisfac y light-Weight Sanding p top plate 16 having a downturned rear end portion which embodies an electric motor operable di- 17, thi being joined to a horizontal bottom plate rectly from the light socket or wall plug, easily 1:; (see Fig. 7) by way of a perpendicular side handled and transported irom place to place and g t 19, The plates 18 and 19 are reiniorced and 25 highly satisfactory for surfacing and recond fu the secured together by way f longitudinally St) tion ng table tops, pamted 9% Surfaces, fuml' spaced transversely extending connective webs ture, school desks, and the like. 20mm 21, these being of general trian u a form In addition to the aforesaid commercial adas illustrated in 7. The web 20 i provided vantages, the machineis further qualified as pOS- t an apertured. boss 22, while the edge of the so sesslng' many manufactullng and assFmblmg web 21 is provided with a clearance notch 23. vantages, such as appreciably csmtrlbute to the Joined to the bottom plate 18 through the medium success and efliciency of the endeavor as a whole. of Spacing abutments 24 is backing plate 25 to Refen'mg now the drawmgs where]? hke which the facing or platen 26 is separably concharacters of reference are employed to designate nected The casing including this frame i prose l p rt throughout e vided at the front end portion with an attaching Figu 1 is an elevatlonal View of a complete ear 2'! which serves a purpose to be hereinafter portable bench sander constructed in accorddescribed ance with the present invention; secured to the top plate near this ear is an F 2 5 a View of h reverse s1de of the appropriate handle or hand grip 28'. The numeral chine represented in Fig. 1 showing the mec 29 designates the horizontally disposed longitudinism visible from this side and showing the dust nany extending motor, t l trical portion of muebtmg bag removedwhich is of ordinary construction. The shell, or top plan View with casing of the motor is of special configuration at bag the rear end portion thereof. As shown for ex- 45 4 15 an elevatmn 0f 1 bservmg 'ampleinFig. 2,the section so is moldedtoembody the same in a direction from left-to right. a rtically elongated gear housing 31 having a fi- 5 i8 Side View of B TemWa-me handle terminal attaching flange 32. On one side of this quipp Imithousing is a cover plate 33 (see Fig. 8) and on the 8- 618 a ragmentary sectiona ew illustratopposite side is a three-part extension.

ing said unit and the associa d dust a assem- One part, indicated by the numeral 34 is fashbly. ioned to accommodate end thrust bearings 35 and Fig. "l is a transverse vertical section through 36 which serve to, support the power take-oi! the lower portion of the frame or chassis. shaft 37. The inner end of this shaft is provided Fig. 8 is a sectional view on the line 8-8 of with a worm gear 38 mesh with a worm drive 39 on the motor shaft 40. The second p1 'body portion of the sprocket drive .enclosure.

44 is a tubular bearing 46 provided with end thrust bearings 47 and 48 to accommodate the shaft 45. The rubber-covered drive pulley 49 is keyed on this shaft 45, and underlies the adjacent end portion 17 of the frame.

I desire now to call attention to the numeral 50 which generally designates the especially fashioned casting constituting an important part of the dust-collector means.- In fact, this unit in cludes a cup 51 fastened to the flange 32 to form a housing for the fan 53, (see Fig. 6). The rim of the cup is provided with a peripheral discharge neck 54 with which the bag 55 (see Fig. 1) is connected. The dust conveying and intake spout is represented by the numeral 56. It is of appropriate configuration, connected concentrically to the cup 51 and has an appropriately designed inlet nozzle 57.

Formed integral with this dust intake nozzle is a rearwardly and downwardly inclined hand grip 58 including a horizontal brace 59. This assembly of details distinguishes the casting 50 as original, and unique, the arrangement being particularly advantageous from a standpoint of simplification of manufacture and assembly.

The aforesaid positively driven pulley 49 serves to accommodate an endless abrasive belt 60, said belt being trained, at its front end, over an idler pulley 61. This pulley 61 is preferablyof the special construction and arrangement depicted in Fig. 9. As represented in the last-named figure, the idler pulley (sometimes referred to broad- 1y as a rotary guide) is cast to provide for selflubrication features. The relatively thick end 62 is recessed to accommodate the end thrust hearing 63 and a packed retaining screw cap 64. The cap 64 is provided with a bushing 65, which takes care of the shaft 66, said shaft 66 being journalled in a bearing 67 on the front end of the adjustable carrier arm 68.

At the opposite end of the pulley is an inwardly spaced diaphragm 69 formed with an oil cup 70 having a removable filler plug 71. Fitted in the diaphragm and cup is a bearing 72. These parts serve to define an oil chamber 73 for effective lubrication results. r

The pulley 61 and carrier arm 68 together with associated parts,.c'onstitutes a unitary assembly, associated with a special belt tensioning and pulley mounting structure. An important part of this structure comprises a fixture generally distinguished by the numeral 74. As seen in Figs. 05

, drical stem 75 having a U-shaped clip 76 at one 10 to 13 inclusive, this fixture embodies a cylinend pivotally connected with shank 77 of the headed end of a slidable plunger rod 78.

The cotter key equipped end of this rod 78 extends loosely through the aforesaid boss 22. Surrounding the rod is an expansion coiled spring 79 bearing at one end against a retention washer 81, and at its opposite end against the headed end of the rod. At its outer end, this stem 75 is formed with a fork whose arms are represented by the numerals 82 and 83 respectively. Rising from the front end of the arm 82 is a standard 84 carrying an elongated eye 85 at its upper end. This eye is mounted for oscillation on a bolt 86 supported in the ear or lug 27. This same bolt 86 passes through a retaining ring 87 forming an integral part of a spring retention clip. This clipincludes a flat spring 88 which bridges the joint between the parts 27 and 85 and is cooperable with a keeper finger 89 carried by the eye 85. The arm 68 is swingably mounted on a spindle bolt 90 located between the arms 82 and 83 and associated with the apertured free end portion of said arm is an adjusting screw 91 threaded into a socket 92 in the stem 75 as seen in Fig. 11.

The numeral 93 designates a thrust spring interposed between the arm 68 and the end of the stem 75. The fixture 74 has a pendulous action and is designed to allow the idler pulley 61 to be moved toward and from the frame to shorten thedistance between the pulley and the main drive pulley to facilitate exchange of abrasive belts.

The inward swinging action of the fixture 74 together with the idler pulley 61 is resented by the spring-pressed plunger arrangement depicted in Fig. 10. This is evident because of the fact that the plunger rod is pivotally and directly connected with the fixture 74 through the medium of the laterally directed stem portion 75. Otherwise stated, the expansion of the spring 79 exerts a resilient end thrust action on the swingable fixture 74 to force the idler 61 into yieldable frictional contact with the interior of the endless belt. Because of this spring tension belt exchange feature, it is essential to have means to maintain the idler pulley in a temporarily tripped state to relieve the endless belt of tension so as to facilitate the exchange. In fact, it is evident that when pressure is brought to bear against the idler 61 it swings in a direction toward the frame and in so doing the keeper lug 89, which is previously beneath the fiat spring 88 as seen in .is of primary importance and regarded as a feature of far-seeing novelty.

The spring 88, keeper 89, and associated details may be referred to as a quick-acting latch arrangement for holding said bracket 74 in a posi-' tion which makes it convenient and easy to replace belts.

I also wish to emphasize the novel lubricating feature of the idler pulley as detailed in Fig. 9, as well as the peculiarity in casting the rear end portion of the motor shell, together with the equally peculiarly shaped unit 50 forming the major portion of the dust collector and fan arrangement.

It is thought from the foregoing description that the advantages and novel features of the invention will be readily apparent.

It is to be understood that changes may be made in the construction and in the combination and arrangement of the several parts, provided that such changes fall within the scope of the" appended claims.

Having thus described my invention, what I claim as new is:- I

l. A machine of the class described comprising a frame, a drive pulley on said frame, means for operating said pulley, a carrier fixture swingably mounted on the frame for forward and rearward pendulous action, a bearing carried by said fixture, an idler pulley including a shaft journaled frame, a hanger bolt carried by a stationary lug on said frame, a fixture embodying an eye mounted for oscillation on said bolt and further including a forked portion operatively connected with the adjacent end of said spring-pressed rod, an idler pulley, a bearing equipped arm operatively connected with said pulley, swingably connected with the forked portion of said fixture, adjusting means between the arm and fixture, a keeper lug carried by said eye, and a spring latch clip carried by said stationary lug, said keeper lug being cooperable with said spring latch clip to maintain the fixture in a predetermined retracted state to resist the tension of the spring-pressed rod.

3. In a machine of the class described, in combination, a frame including. a plurality of walls formed with integral longitudinally spaced transversely disposed webs, one web being apertured and the other web being formed with a clearance notch, a rotatably mounted propulsion drum on said frame, a motor on the frame, an operating connection between the motor and drum, an idler pulley having a projecting joumal at one end, an arm formed with a bearing in which said journal is rotatable, a hanger fixture embodying a vertical standard having a rocker eye at its top formed with a keeper, a fork formed at the bottom of said standard provided with arms between which said first-named arm is pivotally mounted, a horizontally disposed cylindrical stem extending at right angles from said fork into said frame, an adjustable connection between said arm and stem, a rod slidable through the aperture in said web and notch in the remaining web, an expansion coiled spring surrounding said rod to exert a longitudinal yieldable thrust on the rod, and a pivotal operating connection between said rod and stem, together with a bolt carried by the frame on which said eye is rockably mounted, and a spring carried by said bolt with which said keeper is releasably engageable.

4. A machine of the class described comprising a frame, longitudinally spaced front and rear belt guides disposed transversely of said frame, the front guide being in the form of an idler pulley, an endless belt trained over said guides, a horizontally disposed hanger bolt fixedly mounted on the frame adjacent said idler pulley and projecting outwardly beyond the adjacent longitudinal edge of-the frame, a carrier fixture mounted for oscillation on said bolt and having forward and rearward pendulous action outwardly of said frame, relatively stationary resilient latch means co-operable with said fixture to temporarily hold the latter in a retracted position to facilitate exchange of belts, means for pivotally and adjustably connecting one end portion of the idler Dulley to said carrier, and a self-compensating springpressed belt tensioning and thrust means mounted on the frame and operatively connected with said carrier fixture. a

5. A machine of the class described comprising a frame, a stationary lug attached to and rising from the frontal portion of said frame, a hanger bolt carried by said lug and projecting outwardly in a horizontal plane beyond the adjacent edge portion of the frame, a guide pulley carrier fixture having its major portion disposed outwardly beyond the adjacent edge portion of the frame to provide the desired forward and rearward pendulous motion for said fixture, said fixture being mounted for swinging on a horizontal axis on the hanger bolt, a resilient latch clip carried by said lug, said fixture being provided with a keeper lug engageable with said clip, automatically operable spring-pressed thrust means mounted on said frame, an operating connection between the thrust means and the carrier fixture, a bearing arm mounted onf a vertical axis on the carrier fixture, adjusting means for said bearing arm, an idler pulley provided at one end with a journal mounted for rotation in the bearing of said arm, said idler pulley "being disposed'beneath the adjacent frontal portion of the frame and extending transversely of the frame, a transversely disposed longitudinally spaced motion transmitting'pulley on the rear portion of the frame, an endless belt trained over said pulleys,

HARRY L. MYERS. 

